DE69804893T2 - Multi-needle quilt sewing machine for knotted stitch with lower sewing elements with all-round hooks - Google Patents

Description

This invention relates to a multi-needle knot stitch quilting machine with lower sewing elements containing rotating hooks according to the main claim. The invention is applied in the textile, furniture and clothing industries to produce multi-layered quilted textile articles consisting of at least one outer woven fabric and at least one inner support and/or cushioning layer, associated with each other by means of sewing lines which are simultaneously generated to produce desired designs or patterns.

The multi-needle quilting machine according to the invention makes it possible to achieve any kind of pattern, even very sophisticated ones, similar to embroidery and made with stitches arranged very close to each other.

However, with the multiple needle quilting machine according to the invention, it is possible to produce both small and large patterns, and any type of stitch, both single, double, triple, interlocked and double raised, etc.

The state of the art includes multi-needle quilting machines used in the textile industry to produce quilted items using a knot stitch technique.

These quilting machines generally have:

- an infeed arrangement for feeding the multi-layer fabric to be quilted, which consists for example of an outer woven or knitted fabric and at least one inner layer of a supporting and/or cushioning material;

- a quilting arrangement comprising upper quilting elements and lower quilting elements;

- an outlet arrangement to receive and/or measure and/or cut the semi-finished quilted product.

The upper stitching elements of the stitching assembly generally consist of parallel longitudinal rails provided with an alternating raising/lowering movement and carrying a plurality of needles spaced longitudinally from each other at a fixed distance.

Each of the needles is assigned to a respective quilting thread, referred to as needle thread, and interacts with a suitable gripping device provided on the lower quilting elements.

Each gripper has a respective stitching thread, called a bobbin thread. The gripper grips the eyelet or eye of the needle thread and weaves it with the bobbin thread in the desired manner to obtain the desired type of stitch.

In quilting machines of this type, with the knotted stitch, the gripping device can be of two types: a shuttle type or the rotating hook type (crochet needle).

In the first system, a plurality of shuttles are used, each of which carries a bobbin or bobbin of thread, which are made to move alternately forward and backward on slide rails with substantially straight movements, coordinated with the rising/falling movement of the needle carrier rails.

Quilting machines using shuttle-type technology include one, two or three upper needle carrier rails, each of which interacts with a lower row of shuttles.

When three needle carrier rails are used, only two of them are used at a time; the two closest rails are used to make small or average sized designs, and the two farthest rails are used to make large designs.

Given the space occupied by the shuttles, with this type of quilting machine, it is possible to produce quilted items with designs that are very complex, but characterized by quilting lines whose spacing cannot be less than the transverse size of the shuttles and/or the spacing occupied by the slide guide.

However, on multi-needle shuttle type quilting machines, it is possible to mount a needle every inch (2.5 cm) on the relative needle rail to achieve, for example, lozenges or diamonds with a 1 inch cross dimension.

However, the large inertia force of the alternating movement of the shuttles and the sliding friction of the shuttles on the respective sliding rails limits the highest, achievable speed of this type of machine is approximately 600 stitches per minute.

Shuttle-type quilting machines also suffer from other disadvantages, including rapid wear of the shuttles, overheating due to friction between the guides and the shuttles, long downtimes to replace the finished bobbins, and other problems.

Quilting machines with rotating hooks, on the other hand, do not have the above problems and offer higher productivity due to the higher speeds that can be obtained (up to 1000÷1200 stitches per minute using rotating guides made of special anti-friction materials), but on the other hand they do not allow quilted items with very small designs to be achieved.

This is due to the considerable size of the hooks, which prevent closer positioning beyond the physical limit.

The spacing of the lines of stitches is limited to the physical size of the hook itself, and, in machines known in the art, it has therefore never been possible to produce, simultaneously and with all the lower quilting elements, such designs with a spacing between the needles of approximately 2.5 cm (1 inch).

Furthermore, because of the considerable space occupied by the hooks and because of factors related to the cost of a hook rail, it has not been possible to achieve competitive multiple needle quilting machines with more than two rows of hooks, and therefore more than two needle carrier rails, and therefore it has never been operationally possible to achieve both large and small designs on the same machine.

It is known that the quilting pattern is defined by the reciprocating position assumed by the needles in relation to the movement of the material.

The reciprocating position obviously determines the size of the pattern that is achieved.

For example, to produce diamond shapes of 6 inches in cross dimension, two parallel needle rails with needles attached every 6 inches are used; these Needles are stacked and the needles of one rail are interlocked with the needles of the other rail.

The material to be quilted is then moved in a continuous motion forward-left-right-left, each sideways movement covering a space of 3 inches, so that the edges of the zigzag stitches (3 inches wide) made with the needles of the first needle bar touch the edges of the zigzag stitches (also 3 inches wide) made with the second needle bar, thus producing a continuous quilting of diamonds 6 inches across.

In a similar manner, to reach the diamonds with a cross dimension of 3 inches, needles separated from each other by a distance of 3 inches must be fixed on the relative needle rails.

To achieve larger designs, for example 12 inches across, the machine must have three needle bars separated by 3 inches across, with the two outer needle bars having their needles separated by 12 inches and the needles of the first bar nested with the needles of the third bar.

The forward-left-right-left movement of the material to be quilted is therefore 6 inches for each step.

The second intermediate needle rail in this case is excluded from the stitching cycle, however, the installation costs are increased considerably, given the high cost of the hooks.

Accordingly, rotary hook quilting machines are known in the art to make it possible to achieve quilted products with close quilting lines to produce attractive designs or patterns desired by consumers.

In such machines, since the rows of lower stitching elements are stationary and very far apart in order to vary the size of the profile of the desired design, it takes a long time to equip them, especially to re-insert the bobbin with the thread associated with the respective hooks.

To change the size of the design, it is necessary to attach a larger or smaller number of needles and the corresponding hooks in the prescribed, fixed and unchanged positions at the predetermined distances on the respective rails.

Document FR-A-1.526.750 shows a multi-needle quilting machine with rotating hooks; the innovation is essentially that the hooks are mounted with their axes parallel to the needle rails, as opposed to perpendicular to them, the hooks being supported by oscillating arms so as to enable the bobbin to be replaced quickly.

The hooks also have toothed rings on the outer circumference which, when they engage with matching toothed wheels mounted on a central shaft, cause them to rotate.

The purpose of the FR '750 is to reduce the distance between the hooks as much as possible.

However, the positions of the hooks remain fixed and cannot be changed; furthermore, the use of rotating hooks with an axis parallel to the needle rails makes it possible to use pairs of needles working with a single hook to produce a double topstitch seam.

Document JP 71-48366 shows a system for attaching eccentric parts to drive the needles in a multi-needle quilting machine with a needle bar and rotating hooks in such a way that the lateral size of the hooks is limited as much as possible in order to reduce the distance between two adjacent needles.

In this case, the hooks are also attached with their axis of rotation parallel to the needle rail and their position is fixed and cannot be changed.

US-A-5,249,536 shows an embroidery machine with multiple heads; the basic innovation is that there is a system to hold and cut the ends of the threads after stitching.

US '536 also shows a system, now abandoned in modern embroidery machines, of providing for the passage of a rail carrying a head to vary the color of the thread to be connected to the fixed needle.

This document has no relevance with regard to the present invention. US-A-2,483,466 shows a multi-needle quilting machine with a needle bar, probably with rotating hooks; the invention is that there is a mechanical system to move the materials that are under the stationary needles to be quilted to produce patterns of a substantially circular shape.

The position of the hooks is stationary and cannot be changed.

Finally, DE-A-11 46 341 shows a multi-needle quilting machine with a needle rail; the invention lies in the direction of feeding of the materials to be quilted, that is, they are fed in an opposite direction to that used in the conventional machines.

In this case, the position of the hooks is also stationary and cannot be changed. It is clear from the above that none of the prior art documents is able to achieve a solution, especially one with respect to the disadvantages described above.

The present applicant has made, tested and carried out this invention in order to overcome the disadvantages of the prior art that the person skilled in the art has long encountered, and also to achieve further advantages. The invention is set out and characterized in the main claim, while the dependent claims describe variants of the idea of the main embodiment.

The purpose of the invention is to create a multi-needle knot stitch quilting machine that provides a simple and inexpensive solution to produce quilted items characterized by designs that may even be very complex, that are essentially unprecedented in terms of pattern and size and that cannot be produced with traditional machines, with quilting lines that are extremely close to each other.

Another purpose of the invention is to use a single machine to produce both small and large designs, and also designs of a full size, for example halfway between large and small, with a simple and fast, automatic reconfiguration of the position of the upper and/or lower stitching elements.

Another purpose is to use a multi-needle quilting machine with three needle rails associated with only two rails with rotating hooks, which consequently allows small and large designs to be achieved on the same machine, without the additional cost of a third rail which, in the quilting cycles, is just when not in use, nor does it have rotating hooks, so the risks of damage and wear still remain.

Another purpose is to create a machine capable of creating any type of quilting, either single, double or interlaced, double raised, etc., and any type of design very similar to embroidery, by allowing two needles to cooperate with a single rotating hook.

The multiple needle quilting machine according to the invention comprises a quilting assembly with upper quilting elements comprising one, two or three needle carrier rails, and lower quilting elements of the rotating hook type.

More precisely, the lower quilting elements consist of two hook carrier rails, assigned to each other and positioned, at least in a first step of the quilting cycle, corresponding to the needle carrier rails protruding.

According to a first embodiment, the machine according to the invention comprises two hook carrier rails and two respective needle carrier rails.

According to one variant, the quilting machine comprises two hook carrier rails and three needle carrier rails.

The rotating hooks of the at least two hook support rails are freely suspended and axially spaced along a relative longitudinal surface. The rails have at least one first reciprocating working position, with all of the relative hooks being arranged opposite to each other.

According to the invention, at least one of the hook support rails can be translated at least in the longitudinal direction with respect to the other hook support rail. According to a variant, the hook support rail can also be translated transversely with respect to the other hook support rail.

According to another variant, a first hook support rail can be translated transversely and the other hook support rail can be translated longitudinally. By means of the longitudinal displacement of at least one of the hook support rails with respect to the other, which remains stationary, it is possible to misalign the axis of each hook on the first hook support rail with the axis of the respective hook on the second hook support rail by desired values.

By means of this longitudinal displacement of the hooks, it is possible for the needles on the first needle carrier rail to work in a position that is not only aligned transversely to the respective needles on the other rail.

In this way it is possible to vary the distance between adjacent stitchings to minimum values smaller than the space occupied by the hooks, an operation that is not possible in the multi-needle stitching machines currently known.

According to the invention, the needle support rails and the needle plates must have seats to support the needles and the holes through which the needles pass, arranged at a distance which is a sub-multiple of 2.5 cm, reaching values for the interaxial distance as low as 2.5 mm, thus allowing a substantially unlimited multiple of positions for the hooks and enabling the machine to be quickly adapted to the designs to be produced. By means of the transverse displacements of one hook support rail with respect to the other, which remains stationary, it is possible to relate the movable hook support rail corresponding to the third and most spaced hook support rail according to the design to be obtained.

It is therefore possible to use quilting machines with rotating hooks with three needle-carrying rails interacting with only two hook-carrying rails, thus simplifying the machine and obtaining a significant saving, given the high individual cost of the hooks, since there is one hook-carrying rail that is not used.

According to a variant, at least one of the needle carrier rails can be displaced at least transversely, in such a way as to achieve designs of an intermediate size, between large and small.

According to another variant, at least one, and advantageously all, of the needle carrier rails can be displaced longitudinally in accordance with the displacement of the corresponding hook carrier rail, so as to avoid the need to reposition the needles when a hook carrier rail is displaced longitudinally.

If it is desired to change from the small design configuration to the large design configuration, the hook carrier rail, which is moved transversely can be moved and aligned to the third and furthest needle carrier rail, while the others remain stationary in their position.

This solution also avoids downtime due to re-insertion and replacement of the coils, as required in the state of the art every time the configuration of the machine is changed.

According to the invention, each hook carrier rail cooperates with a respective motor device which is suitable for rotating all hooks attached to the rail simultaneously and synchronously with the raising/lowering movements of the needle carrier rail.

According to a variant, the hook support rails cooperate with braking devices that allow the hooks to be maintained in a gradation relative to one another both during the machine's downtimes and during the fitting step and also during the longitudinal and/or transverse translations of at least one of the hook support rails.

According to one possible embodiment, the braking devices interact at least with the motor device of the hook carrier rails.

According to the invention, the hook support rails cooperate with a longitudinal guide device and a transverse guide device and are advantageously, but not exclusively, of a servo-controlled type, which consequently enables the fitting and adaptation operations to be carried out quickly and automatically. According to a possible embodiment of the invention, the translation movements of the hook support rails take place in steps.

With this invention, thanks to the fact that it is possible to reduce to a minimum the longitudinal distance between the hooks fixed on the different rails and due to the use of pairs of needles working with the same hook, it is possible to obtain double stitches in a position of proximity up to 2.5 mm low, normal or raised, knotting the threads of the two adjacent needles by the thread of a single hook.

The multiple needle quilting machine according to the invention comprises a device for feeding the material to be quilted, electronically controlled and managed by software which enables any type of quilting design to be achieved.

The attached figures are given as a non-limiting example and show a preferred embodiment of the invention as follows:

Fig. 1 is a three-dimensional view of a multiple needle quilting machine according to the invention;

Fig. 2 represents a longitudinal section of the machine in Fig. 1;

Fig. 3a, 3b, 3c each show three possible configurations of the lower quilting elements of the machine in Fig. 1;

Fig. 3d, 3e, 3f respectively illustrate the lower quilting elements in the configurations shown in Fig. 3a, 3b, 3c when placed in cooperation with the upper quilting elements;

Fig. 4 shows a partial view of the enlarged detail A of Fig. 2;

Fig. 5 is a partial top view of Fig. 2;

Fig. 6a is a partial view of an enlarged detail of the lower quilting elements shown in Fig. 5;

Fig. 6b and 6c show variants of Fig. 6a;

Fig. 7 shows a partial view of a side of Fig. 5;

Fig. 8 shows a variant of Fig. 7.

Fig. 1 shows a multiple needle quilting machine according to the invention.

The multiple needle quilting machine 10 comprises, in its essential parts, an inlet arrangement 10a, a quilting arrangement 10b and an outlet arrangement 10c.

The infeed assembly 10a is used to feed the textile material 11 to be quilted; the material 11 in this case consists of an upper fabric 11a, a lower fabric 11c and an intermediate layer of a backing and a padding 11b, so as to form a so-called "quilted sandwich".

The infeed assembly 10a is managed and controlled by a software unit and is therefore able to move the textile materials 11 in any direction so as to obtain quilted products 19 with designs that may even be very complex. The quilting assembly 10b comprises upper quilting elements 12 consisting of needle carrier rails 13 lying parallel to each other, in this case three in number, 13a, 13b and 13c respectively, which cooperate with matching lower quilting elements 15. The needle carrier rails 13 are provided with respective movement arms 26 equipped with an alternating raising/lowering movement and have a A plurality of quilting needles 24, each of which cooperates with a respective thread 14, known as a needle thread.

The cooperation between the upper quilting elements 12 and the lower quilting elements 15 causes the simultaneous formation on the textile material 11 of a plurality of stitches 18 to achieve the desired designs to obtain a quilted textile product 19 which is then assembled in the desired manner at the outlet assembly 10c.

According to the invention, the assemblies 10a, 10b and 10c are controlled and activated by an electronic control unit 25 equipped with an interface device, such as a keypad, a display, possible peripheral printing machines or the like, with which the operator can interface the multi-needle quilting machine 10.

In this case, the lower stitching elements 15 consist of two parallel hook carrier rails 16 arranged in a matching position to two of the needle carrier rails 13 above.

Each of the hook support rails 16, the first rail 16a and the second rail 16b, respectively, cantilever a plurality of rotating hooks 17, essentially of a structure and function known in the art, having an axis of rotation substantially perpendicular to the relative rail 16a, 16b.

In this case, the rotating hooks 17 are mounted in alignment along the length of the outer side 116a and the outer side 116b of the respective hook support rails 16a and 16b; the inner sides 216a and 216b of the hook support rails 16a and 16b are therefore arranged opposite one another, so that the two hook support rails 16a and 16b comprise at least a first working position where they are mirror images of each other (Fig. 3a, 3d).

Each hook carrier rail 16 cooperates with a respective motor device 20, in this case comprising a drive belt 21, which is suitable for causing the hooks 17 to rotate simultaneously, in gradations relative to one another and synchronously with the alternating raising/lowering movements of the needles 24 of the respective needle carrier rails 13 (Fig. 2, 4).

In this case, the hook support rail 16b can be moved both longitudinally and transversely with respect to the other hook support rail 16a, which remains stationary.

According to a variant not shown here, both hook support rails 16a and 16b can be translated both longitudinally and transversely.

According to a further variant, which is not shown here, the hook carrier rail 16a or 16b can only be translated in the longitudinal direction and the other hook carrier rail 16b or 16a can only be translated transversely.

In the case shown here, the hook support rail 16b comprises a first working position (Fig. 3a, 3d) where it is in contact with the rail 16a and where the respective hooks 17 are opposite to the hooks 17 on the hook support rail 16a.

In this position, the hook support rails 16a and 16b cooperate with the needle support rails 13a and 13b (Fig. 3d) so as to achieve small designs and with stitching lines spaced at a distance not less than 2.5 cm (1 inch). The hook support rail 16b may also have a second working position (Fig. 3b, 3e) shifted longitudinally to the rail 16a by a value D so as to arrange the respective hooks 17 at an offset position with respect to the hooks 17 on the hook support rail 16a.

This shifted position makes it possible to achieve small designs, given the reciprocating transverse position of the rail 16a, 16b; however, the stitching lines that can be achieved are closer to each other, at a distance that is a sub-multiple of 2.5 cm, according to the value of the gradation of the respective hooks 17.

In this configuration, with the hooks 17 displaced, the needles 24 of the needle carrier rail 13b are positioned in accordance with the new position assumed by the hooks 17, using auxiliary seats 29 arranged in a suitable manner on the needle carrier rail 13b.

The hook support rail 16b may further have a third working position, displaced transversely by a value S with respect to the hook support rail 16a, in such a way as to enable it to be positioned corresponding to the third and most distant needle support rail 13c, so as to achieve large size designs (Fig. 3c, 3f, 7).

The longitudinal and transverse shifts can be further combined to obtain large designs with close stitching lines, or any other type of combination, which is desired. A new value of a transverse distance S1 of the hooks 17 (Fig. 6c) corresponds to the value S of the transverse displacement with respect to the rails 16a, 16b. According to the variants shown in Fig. 8, at least one of the needle carrier rails 13a, 13b, 13c can be moved in a transverse direction, in this case the needle carrier rail 13c.

This solution, in which the needle carrier rail 13c has a transversely displaced position, represented by a broken line 113c, makes it possible to achieve the designs of an intermediate size, between small designs made with the needle carrier rail 13a and 13b, and large designs made with the needle carrier rail 13c in its position as given by the solid line.

In this case, the transverse movement is achieved by a sliding device element 17, fixed to the needle carrier rail 13c and able to slide along a guide 28.

According to another variant, which is not shown, the needle carrier rail 13a and/or the needle carrier rail 13b can also be displaced transversely.

According to a further variant not shown here, at least one of the needle support rails 13a, 13b and 13, and advantageously all of them, can be moved longitudinally according to the longitudinal movements of the relative hook support rails 16, so as to constantly and automatically maintain the alignment between the needles 24 and the relative hooks 17 in all their longitudinal positions.

In this way it is possible to significantly reduce the times required for adjusting and reconfiguring the machine in each working position and for each size of the designs to be produced.

In this case, the hook carrier rails 16 are translated automatically by means of servo controls or manually by the operator while the multi-needle quilting machine 10 is being equipped and configured.

During the fitting step, according to the invention, braking devices, for example of the electromagnetic or pneumatic type, intervene; the braking devices cooperate with at least the motor device 20 and have the function of maintaining the hooks 17 in a gradation with respect to one another and consequently of allowing the multi-needle quilting machine 10 to be immediately restarted.

In the case shown in Fig. 5, in cooperation with the hook carrier rail 16b, there are guide devices 22 which cooperate in a longitudinal displacement and guide devices 23 which cooperate in a transverse displacement.

According to an embodiment of the invention, the translations take place in a gradation according to the predetermined values S and D.

According to a variant, the translations take place continuously with values S and D, which can be set from time to time by the operator by means of the electronic control unit 25, for example.

According to the invention, the combination of the longitudinal/transverse displacements of one hook-carrying rail 16b with respect to the other rail 16a with the movements of the textile material 11 fed by the infeed assembly 10a makes it possible to achieve any kind of quilting whatsoever, and therefore any kind of design or embroidery whatsoever, which has never been achievable so far with the machine known in the prior art using the rotary hook technology.

More specifically, the invention makes it possible to achieve a distance D between the rotation axes of the corresponding hooks 17 and therefore between the needles 24 of the corresponding needle support rails 13, less than the size of the maximum space occupied by the hooks 17.

Furthermore, using only two hook carrier rails 16, it is possible with this invention to use three needle carrier rails 13 so as to obtain designs of both large and small size.

The transverse displacement of at least one of the needle carrier rails 13 also makes it possible to achieve designs of a size between the large size and the small size.

The combination of the movements of the hook support rails 16, the provision of multiple seats 29 on the needle support rails 13 and the possibility of transverse and/or longitudinal displacement of the needle support rails 13 themselves makes it possible, all of these factors, to produce double stitches of the smooth type, the raised type, the alternating type, the interlocking type, triple stitches or -quilting or even a mixed type, each with single, double or triple stitch, using the same hook.

Claims (11)

1. A multi-needle knot stitch quilting machine with lower sewing elements containing rotating hooks, the machine comprising an inlet assembly for the controlled feeding of the textile material (11) to be quilted, a sewing assembly containing upper sewing elements (12) and lower sewing elements, and an outlet assembly which receives and possibly measures and cuts the quilted product (19), the upper sewing elements comprising at least two parallel rails (13) arranged longitudinally and carrying the corresponding sewing needles (24) in a longitudinally spaced position, the lower sewing elements with rotating hooks (17) being arranged in longitudinal rows corresponding to the position of the corresponding needle carrier rail (13), the position of each needle (24) corresponding to the position of a corresponding rotating hook (17), and the machine having the rotating hooks (17) spaced longitudinally at a predetermined Mounting distance on the corresponding surfaces (116a, 116b) of at least two longitudinal rails (16a, 16b), the machine being characterized in that at least one of the hook support rails (16a, 16b) can be displaced longitudinally with respect to the other rail (16a, 16b) by a value (D) corresponding to a desired fraction of the mounting distance of the rotating hooks (17) on the corresponding rail (16a, 16b). 2. Machine according to claim 1, wherein at least when three needle carrier rails (13) are used, at least one hook carrier rail (16a, 16b) can be displaced transversely with respect to the other hook carrier rail (16b, 16a) and in this transversely displaced position the hook carrier rail aligns the corresponding hooks (17) with the furthest away of the needle carrier rails (13c). 3. Machine according to claim 1 or 2, wherein the same hook carrier rail (16b, 16a) can be displaced both transversely and longitudinally to the other hook carrier rail (16a, 16b). 4. Machine according to claim 1 or 2, wherein a first hook carrier rail (16b, 16a) can only be moved longitudinally and a second hook carrier rail (16a, 16b) can only be moved in a transverse direction. 5. Machine according to one of the preceding claims, wherein at least one needle carrier rail (13a) can be displaced transversely with respect to the adjacent needle carrier rail (13b). 6. Machine according to one of the preceding claims, wherein at least one needle carrier rail (13c) can be displaced longitudinally. 7. Machine according to one of the preceding claims, wherein at least one needle carrier rail (13) includes additional receptacles (29) for arranging needles (24) in relation to the position that can be assumed by the hooks (17) in the longitudinally displaced position of the corresponding hook carrier rail (16). 8. Machine according to one of the preceding claims, wherein, in order to carry out particularly close sewing, two needles (24) cooperate with a single rotating hook (17). 9. Machine according to one of the preceding claims, wherein each hook carrier rail (16) is connected to a corresponding motor device (20) in order to move all hooks (17) simultaneously. 10. Machine according to one of the preceding claims, which cooperates with an electrical control unit (25) to adjust the configuration of the machine (10) and the size and profile of the seam to be produced. 11. Machine according to one of the preceding claims, which enables different seams, i.e. double seams, triple seams, raised double seams, smooth double seams, covered seams, etc., of large and small size, wherein a distance between the corresponding lines of the seams corresponds to a desired fraction of the mounting distance of two adjacent hooks (17).